1. Field of the Invention
The present invention relates to a tenprint card reader for use in inputting fingerprint images printed on a tenprint card to a computerized fingerprint collation system.
1. Description of the Related Art
In general, collation of fingerprint images by a computerized fingerprint collation system is carried out by inputting and processing each individual's ten fingerprint images printed on a tenprint card one fingerprint at a time.
A common tenprint card, on which fingerprints are printed, is approximately 20 centimeters square in area. The tenprint card is typically composed of a rolled fingerprint section on which a rolled fingerprint of each finger is to be printed and a plain fingerprint section on which a plain fingerprint of each finger is to be printed. Herein, the rolled fingerprint represents a print taken of a rolling finger and the plain fingerprint represent a print of a finger taken without rolling.
The rolled fingerprint section is made up of ten corresponding to the individual's ten fingers, each having an area of some 4 centimeters square. The plain fingerprint section is made up of a thumb region on which a plain fingerprint of the thumb is to be printed, and a four-finger region on which plain fingerprints of four fingers, the forefinger, the middle finger, the ring finger and the little finger, are printed all together. The tenprint card is capable of containing fingerprints of a total of 20 fingers in the above-described respective regions. The size and the position of the respective regions of the rolled fingerprint section and the plain fingerprint section may slightly vary with the kind of tenprint card.
During fingerprint image collation by a computerized fingerprint collation system, an image within an area approximately 2.6 centimeters square is first cut out of a fingerprint image of each finger printed on the above-described tenprint card. The image includes a core of the fingerprint. The subsequent collation processing is economically carried out with respect to the fingerprint image data contained within this cutout range.
A fingerprint image cutout processing device is used for cutting and sequentially inputting fingerprint images of ten fingers to be collated out of the tenprint card.
A conventional fingerprint image cutout processing device for a tenprint card cuts out rolled fingerprints of the tenprint card within the above-described cutout range and inputs the cut-out fingerprint images to a fingerprint collation system one fingerprint at a time. The fingerprint image cutout area of each finger is determined prior to fingerprint image collection by inputting numerical location data of each rolled fingerprint section on the type of tenprint card to be used. In other words, by adjusting a scan area for reading each fingerprint image based on the given location information, the conventional device cuts out and sequentially inputs a fingerprint image within the area of a square having one side parallel to a scan line.
However, it is more difficult to use fingerprint cards which have rolled fingerprint sections at different locations or the cards to change a cutout position of cards which have a rolled fingerprint section at the same location. A conventional tenprint card reader for use with the above-described fingerprint image cutout processing device will then require input of location information as numerical data before reading each of the cards. This requires more processes and time for the numerical location data acquisition and verification of input results.
When the conventional device scans a plurality of tenprint cards each having a rolled fingerprint section at the same location, the conventional device automatically cuts out fingerprints according to the same cutout position designation. Nevertheless, the cutout area tend to have partially missing fingerprints when the fingerprints are displaced toward the edge of a square region of some 4 centimeters square.
In a case where a rolled fingerprint is of poor quality and the corresponding plain fingerprint is of high quality, collation accuracy can be improved by cutting out the plain fingerprint. However, the conventional device does not provide the opportunity to change a selected position of the cutout area.
With a skewed fingerprint in a fingerprint registration region of the rolled fingerprint section, it is impossible for the conventional device to cut out the fingerprint by rectifying the direction of its fingertip.
Another conventional fingerprint image input device for use with the above-described fingerprint cutout processing device is a oneprint image input device which inputs fingerprint images one fingerprint at a time. When inputting fingerprint images from a tenprint card using the oneprint image input device, an operator shifts the tenprint card for each finger and adjusts the area of the fingerprint image to be cut out to a scan position of the device. With the oneprint image input device, it is possible to overcome the above-described shortcomings of the conventional fingerprint image cutout processing device for a tenprint card.
During fingerprint image input by the oneprint image input device, however, the tenprint card should be manually shifted to ensure an optimum scan position every time an image is to be input for each finger. This operation is time-consuming and a burden on an operator.